Generally heavier 1/2" wads, lubed or not, placed under the shot, will blow the patterns.
The Skychief load has a heavily lubed 1/2" wad OVER the shot and this does not blow the patterns, usually,
or this type of load would lack it's obvious popularity. What it most effectively does, is lubricate the bore and
the shot charge being discharged., which is why many use Olive Oil for the lube.
Mixed shot is common with a lot of people. Even some modern companies mix shot sizes, usually 4's and 6's
for the current brand I am thinking about.
Smaller number, larger and fewer pellets in a given volume or weight of shot charge. The finer the shot(larger #),
the greater the chance of striking the spine and brain.